In recent years, the global positioning system (GPS) has been instrumental in advancing the practical utility of satellite communications in a variety of applications. In order to take full advantage of the capabilities offered by GPS satellite transmissions, antennas that provide a right hand circular polarization are necessary. Good coverage near the horizon is also necessary so that low elevation satellites can be effectively tracked. Antennas having crossing slots have been proposed, as have a variety of cylindrical slot antennas. Slot antennas typically include slots that are uniform in width and are used with microstrip feed systems. Cylindrical slot antennas have many advantageous characteristics, including broad beam pattern production, light weight, amenability to mass production, and simple feeding and matching techniques. However, the cylindrical slot antennas that have been proposed in the past have not been entirely satisfactory with respect to their ability to provide effective horizon coverage of low elevation signals.